[JS IR] Improve debug info precision for blocks

Namely:
- Generate debug info for closing braces, which allows the breakpoints
  set on closing braces to be hit
- Generate debug info for 'if' and 'try/catch' statements.

KT-46276

compiler/testData/debug/stepping/initBlocksCompanion.kt

@@ -60,4 +60,6 @@ fun box() {
 // test.kt:13 <init>
 // test.kt:16 <init>
 // test.kt:21 <init>
-// test.kt:30 box
+// test.kt:4 <init>
+// test.kt:30 box
+// test.kt:31 box